Building on a slab has a few advantages and several disadvantages. By building on a slab is meant pouring a concrete slab over the area of the house, around which walls are built and over which the roof is placed. The slab, with suitable floor coverings, forms the floor of the house.

The advantages might be listed about as follows: it is more fireproof than other methods of construc­tion, as there is no space under the floor and the con­crete is, of course, fireproof. It is less expensive to build and quicker to construct. The floor is quiet; the house can be built closer to the ground. The floors are not springy and they do not squeak.

Some of the disadvantages will be noted as we discuss the floor finishes, and others will occur to the reader as he ponders the problem. The ants find it easier to get into a slab house as it is closer to the ground. The water pipes are often concealed beneath the floor, where it is impossible to service them. Heating problems are more difficult with a slab floor. Termites are harder to control as the house is so close to the ground. If you should ever have to move the house, it would be more difficult.

Although there are certain economies that re­sult from building on a slab, a few difficulties are also encountered.

The actual foundation costs about the same either way you do it, but it is less expensive to pour a con­crete slab than it is to frame a wood floor, both for material and labor. If a person is capable of framing the floor, but would find pouring the slab too much for him, the wood floor might be cheaper for him. Also the cost of the two types of construction vary in different localities, so that in some places the wood might actually be cheaper.

In pouring a concrete slab, care must be taken to make sure that moisture will not come through the slab. Plastic sheets have lately been developed that when spread over the entire surface under the con­crete, quite effectively exclude moisture from the floor. Sometimes a layer of gravel 4" thick is a great help in keeping the capillary action from bringing moisture to the concrete slab. In cold sections of the country perhaps it is best not to use the slab con­struction, at least unless special precautions are taken to control the heat, cold, and moisture situation. Some kind of insulation most certainly would be needed to keep the frost from coming in around the outside walls, as concrete, which is a very good con­ductor of heat, will conduct heat out of a house ra­pidly when the weather is cold.

While it is advisable to avoid slab floors in cold or wet districts, in warm dry climates they seem to be quite successful. There are several finishes that should be considered for concrete floors, several of which will be mentioned here. Asphalt tile is the most widely used since it is not expensive, will stay in place in spite of moisture, wears well, comes in many at­tractive colors, and requires a minimum of upkeep. It does make a rather hard floor, which some people say is very tiring to the feet when a person has to stand on it for long periods of time. Oils, fats, paste waxes, and similar materials will soften and partially dis­solve asphalt tile, which makes it unsuitable for kit­chen floors.

Although linoleum is a good floor covering, if the concrete is not properly waterproofed the lino­leum will not stay in place on it. Sometimes when linoleum does not get moisture from below, it will condense it from the air. The concrete, a good con­ductor of heat, when on cold ground will tend to be cold. Thus the warm moisture-laden air deposits condensation on the cool surface of the linoleum; enough moisture can collect to swell the linoleum and cause it to buckle. Note how moisture collects on the outside of a glass of ice water.

It is almost impossible to cushion a floor on con­crete successfully. Either it will be too soft and spike heels will dent it, or it will not be soft enough to be satisfactory, or the cushion will swell and buckle, or something seems always to be wrong with it. There is, however, a new very thin cushion of sponge rub­ber that gives promise of being successful, made es­pecially to cushion linoleum.

Oak parquet blocks can be laid in a waterproof mastic on a concrete floor with good effect and very few problems.

Vinyl asbestos tile seems to do fairly well on a concrete floor.

Burned tile, quarry tile, ceramic tile, etc., are ideal over concrete for bathrooms, hallways, laundry rooms, patios, porches, etc.

Carpet can be put on a concrete slab very suc­cessfully. After the concrete is thoroughly water­proofed, or even if not quite so well done, a good hair felt or rubberized pad is put on the concrete. A rug is then stretched over this to make a very satis­factory floor, warm, resilient, and comfortable.

Here is a suggestion for floor finishes in a house built on a slab: slate floors on the porches and in the entrance hall; ceramic tile in the back hall, in the laundry, in the bathrooms and on the patio; oak parquet floors in the dining room and in the den; cushioned linoleum in the kitchen; wall-to-wall car­pet in the living room; asphalt tile, vinyl asbestos tile, oak parquet blocks, or wall-to-wall carpet in the bedrooms.

Incidentally, most of the tract houses I have seen lately are using asphalt tile floors almost exclusively; once in awhile you find a kitchen floor of vinyl tile. Some of the tract houses leave the concrete exposed in the living room with the idea that the owner will use carpet on the floor.

Advantages of Building on a Wood Frame Floor

If you use a wood frame under the floor, it is more resilient and easier on the feet, inclined to be warmer, and it is easier to install satisfactory finish floors and floor coverings. You can get under to serv­ice or repair the plumbing. The house could be moved if necessary. The first item is often the de­ciding factor, as the resilient floor is so much easier on your feet and is not so much inclined to be cold.

The disadvantages may be that the floor is not fireproof, that it is slightly more expensive to build, that it takes more time and work, and if the space under the floor is not properly ventilated, the joists and floor may be damaged by so-called dry rot or by termites.

The average beginning builder is perhaps better off not to undertake building on a slab unless he is willing to investigate the local conditions carefully and study every problem in connection with it, as it has many pitfalls.

Since concrete is a good conductor of heat, in a very cold country the heat is liable to escape around the outside walls, causing frost to form on the floor just inside the walls. This might be partly overcome by properly placed insulation, but insulation in this position could easily become damp and thus inef­fective. In places where many people are building satisfactory houses on slabs, go ahead and follow, but pioneering in a new place where conditions are different could be hazardous. Soil, moisture, temper­ature, the kind of concrete, and the climate all have such a bearing that it is often wise to let others do the expensive experimenting involved in building a new kind of house. A house is too expensive a propo­sition for the average person to use in experimenting with novel ways of doing things. This is not to say that many of our building methods could not well be improved, but to suggest that we let the experiment­ing be done by those who can afford to do it.

Another thing that must be remembered is that the local building codes often have not caught up with some of the newer methods, and the loan com­panies are even more conservative, when it comes to something out of the ordinary or different from that which they are accustomed to seeing done.